the thing is that the likes count in the app that the company made.
to make it clear
There is a contest in facebook that you have to upload a photo in instagram and tag 2 words. As soon as the photo is properly tagged it shows up in facebook in the contest page. The contest has nothing to do with facebook. It is made and hosted within facebook but from another compan as with most contests in facebook

so,
I upload a photo in instagram
with proper tag it show up in facebook. in the contest page
There are two ways to get likes for the photo
1 from facebook, and 1 from instagram
I was able to like my photo in facebook, within the contest and using firebug i was able to see the post command that is sent when i vote that photo from within facebook. It is an ajax.php with data vote&photoid=25. to a specific url that hosts the contest
If i want to vote from instagram i have to go to the instagram website and then i cannot see the post command not to instagram but to the site that hosts the contest

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